Experiencing the resonant acoustics of the church of Hagia Sophia allowed the Byzantine participants in its liturgical rituals to be filled with the Spirit of God, and even to become his image on earth. Bissera Pentcheva's vibrant analysis examines how these sung rites combined with the church's architectural space to make Hagia Sophia a performative place of worship representative of Byzantine religious culture in all its sensory richness.Coupling digital acoustic models and video with a close examination of liturgical texts and melodic structures, Pentcheva applies art-historical, philosophical, archeoacoustical, and anthropological methodologies to provide insight into the complementary ways liturgy and location worked to animate worshippers in Byzantium. Rather than focus on the architectural form of the building, the technology of its construction, or the political ideology of its decoration, Pentcheva delves into the performativity of Hagia Sophia and explains how the "icons of sound" created by the sung liturgy and architectural reverberation formed an aural experience that led to mystical transcendence for worshippers, opening access to the imagined celestial sound of the angelic choirs.Immersive, deeply researched, and beautifully illustrated, this exploration of Hagia Sophia sheds new light on sacred space, iconicity, and religious devotion in Byzantium. Scholars of art and architectural history, religious studies, music and acoustics, and the medieval period will especially appreciate Pentcheva's field-advancing work.